1. Technical Field
The present invention relates to a manufacturing method of a laminated iron core formed by folding a strip-shaped iron core piece in a joint and spirally winding and laminating the strip-shaped iron core piece in which segment iron core pieces are connected through the joint.
2. Background Art
For example, JP-A-2011-188651 discloses a manufacturing apparatus 84 of a laminated iron core in which a strip-shaped iron core piece 82 in which segment iron core pieces 80 are connected through a rotatable joint 81 is folded in the joint 81 and is spirally wound and also is crimped and laminated through crimp parts 83 formed on the segment iron core pieces 80 as shown in FIG. 5. In a case of manufacturing the laminated iron core using this manufacturing apparatus 84, when the strip-shaped iron core piece 82 is folded in the joint 81, a bulged portion occurs in a thickness direction of the joint 81 and a gap occurs between the vertically adjacent segment iron core pieces 80 due to this bulged portion and variations occur in thickness of the obtained laminated iron core.
Here, reference numeral 85 is a conveyance lane for guiding the strip-shaped iron core piece 82 to a winding start position, and reference numeral 86 is a pilot pin for positioning the segment iron core piece 80, and reference numeral 87 is an insertion hole of the pilot pin 86, and reference numeral 88 is a press roller for pressing the strip-shaped iron core piece 82 moving along the conveyance lane 85 from above, and reference numeral 89 is a drum for supporting the wound and laminated strip-shaped iron core piece 82 from the inside, and reference numerals 90, 91 are a side press roller and an upper side press roller respectively abutting on the outer periphery and the uppermost part of the strip-shaped iron core piece 82 wound and laminated. Also, reference numeral 92 is a push pin for pressing the crimp part 83 of the segment iron core piece 80 of the uppermost part and crimping and laminating the crimp part 83 to the segment iron core piece 80 of the lower side, and reference numeral 93 is a crimp mold including the pilot pins 86 and the push pins 92.
Because of this, for example, Japanese Patent No. 4150397 describes a situation in which when a strip-shaped iron core piece 96 in which segment iron core pieces 95 are connected through a joint 94 is folded in the joint 94 and is spirally wound and also the vertical segment iron core pieces 95 are crimped and laminated and a laminated iron core 97 is formed, the outer peripheral side of the segment iron core piece 95 is previously provided with a receiving part 98 made of a notch or a hole and bulged portions 99 occurring in the folded joint 94 are received in the receiving parts 98 of the vertically arranged segment iron core pieces 95 and thereby a gap between the segment iron core pieces 95 is prevented from occurring as shown in FIGS. 6A and 6B.
Also, Japanese Patent No. 3171303 discloses a laminated iron core 104 for stator in which by thinning a joint 101 through which partial yoke iron core pieces 100 are connected, a relief part 103 for receiving a bulged portion 102 formed in the case of folding the joint 101 is previously formed inside the partial yoke iron core piece 100 and a gap (an increase in distance of lamination) occurring in the case of laminating the partial yoke iron core pieces 100 is prevented and a decrease in crimp strength is prevented as shown in FIG. 7.